In `MgSO_(4)` (at. mass : Mg = 24, S = 32, O = 16), the mass percentage of

Options

A. Mg = 80%
B. Mg = 20%
C. S = 26.7%
D. S = 53.3 %

Explanation

To find the mass percentage of Magnesium (Mg) and Sulfur (S) in Magnesium Sulfate (MgSO₄), we will follow these steps:

### Step 1: Calculate the Molar Mass of MgSO₄
- The molar mass of MgSO₄ is calculated by adding the atomic masses of its constituent elements.
- Atomic mass of Mg = 24 g/mol
- Atomic mass of S = 32 g/mol
- Atomic mass of O = 16 g/mol (and there are 4 oxygen atoms in MgSO₄)

**Calculation:**
\[ \text{Molar mass of MgSO₄} = \text{Mass of Mg} + \text{Mass of S} + 4 \times \text{Mass of O} \]
\[ = 24 + 32 + 4 \times 16 \]
\[ = 24 + 32 + 64 \]
\[ = 120 \text{ g/mol} \]

### Step 2: Calculate the Mass Percentage of Sulfur (S)
- The mass percentage of an element in a compound is given by the formula:
\[ \text{Mass \% of element} = \left( \frac{\text{Mass of element}}{\text{Total mass of compound}} \right) \times 100 \]

**Calculation for Sulfur:**
\[ \text{Mass \% of S} = \left( \frac{32}{120} \right) \times 100 \]
\[ = \frac{32 \times 100}{120} \]
\[ = \frac{3200}{120} \approx 26.67\% \]

### Step 3: Calculate the Mass Percentage of Magnesium (Mg)
**Calculation for Magnesium:**
\[ \text{Mass \% of Mg} = \left( \frac{24}{120} \right) \times 100 \]
\[ = \frac{24 \times 100}{120} \]
\[ = \frac{2400}{120} = 20\% \]

### Final Results
- Mass percentage of Sulfur (S) in MgSO₄ = **26.67%**
- Mass percentage of Magnesium (Mg) in MgSO₄ = **20%**